<template>
    <div class="person">
        姓：<input type="text" v-model="firstName">
        名：<input type="text" v-model="lastName">
        <button @click="changeFullName">将全名改为li-si</button> <br>
        全名：<span>{{ fullName }}</span> <br>
        全名：<span>{{ fullName }}</span> <br>
        全名：<span>{{ fullName }}</span> <br>
    </div>
</template>

<script lang="ts" setup name="Person">
import { ref, computed } from 'vue';

let firstName = ref('zhang')
let lastName = ref('san')

// fullName是一个计算属性，且是只读的
/* let fullName = computed(()=>{
  console.log(1)
  return firstName.value.slice(0,1).toUpperCase() + firstName.value.slice(1) + '-' + lastName.value
}) */

// fullName是一个计算属性，可读可写

//   let fullName = computed((newVal,oldVal)=>{
//     return firstName.value.slice(0,1).toUpperCase() + firstName.value.slice(1) + '-' + lastName.value
//   })
let fullName = computed({
    get: () => firstName.value.slice(0, 1).toUpperCase() + firstName.value.slice(1) + '-' + lastName.value,
    set: (val) => {
        const [str1, str2] = val.split('-')
        firstName.value = str1
        lastName.value = str2
    }
})

// 方法
function changeFullName() {
    fullName.value = 'li-si'

}
</script>

<style scoped>
.person {
    background-color: skyblue;
    box-shadow: 0 0 10px;
    border-radius: 10px;
    padding: 20px;
}

button {
    margin: 0 5px;
}

li {
    font-size: 20px;
}
</style>